1. Field of the Invention
The present invention relates to an improvement in drawer locks and, more particularly, to an improvement in drawer locks for use in a cabinet which contains more than one drawer. The present enables the drawn out drawers to be closed and automatically locked again after the cabinet has been latched and locked.
2. Description of the Prior Art
In a conventional tools or articles cabinet, there is usually provided casters at the bottom thereof to enhance its mobility. In addition to this, the drawer may be opened and drawn out for easily accessing things held in the drawer.
However when more than one drawers are opened and drawn out, it might result in the entire cabinet being tilted over to one side because of the unbalanced weight thus causing people to be hurt. To prevent this from happening, there is often provided a safety drawer lock which allows only one drawer to be opened and drawn out at a time. FIGS. 1 and 2 show such an example. It includes a cylinder 1, a trigger bar 2, a fixing block 3, a sliding block 4, a first elastic member 5, a latch hook 6 and a latch bar 9. The rear end of the cylinder 1 has a first slot 11 engaging with a front end of the trigger bar 2. The rear end of the trigger bar 2 goes through the fixing block 3 and engages with the sliding block 4 which is slidable transversely. The sliding block 4 is a -shaped frame having an opening 41 running through the top and bottom flanges, and two spaced second and third slots 42 and 43 formed in a lateral wall. The trigger bar 2 has its rear end engaged with the second slot 42. The third slot 43 is engageable with a spring blade 44 which is fixed to an inside surface of the sliding block 4. The latch bar 9 is an elongated plank with a plural number of latch openings 91. At a lateral side of the latch bar 9, there is provided a spindle 92 with two ends extending out of the plank. At another lateral side of the latch bar 9, there is a strut 93 with one end extending out of the plank. The first elastic member 5 has two ends engaging respectively with the strut 93 and the fixing block 3. The latch hook 6 fixed to a drawer 7 is a plate with a hooking slot 61, a left slant edge 63, a right slant edge 64 and a finger 62.
When in use, a key is inserted into the cylinder 1 and turned clockwise. The trigger bar 2 is also being turned and moves the sliding block 4 to the left. The spring blade 44 pushes the strut 93 and turns the latch bar 9 to a preset angle clockwise. The latch opening 91 disengages with the finger 62 on the latch hook 6. The drawer 7 is then free to open and draw out.
When one of the drawers is drawn out, the left slant edge 63 will move against the latch bar 9. With the aid of the first elastic member 5, the latch bar 9 is pushed to the locking position to lock all other drawers that are not opened.
By means of such arrangements, only one drawer is allowed to open and be drawn out at one time. Therefore, it can prevent two or more drawers from being drawn out and causing the cabinet to tilt, because of unbalanced weight. However when a user incidentally turns the cylinder 1 counter clockwise, the trigger bar 2 will turn and move the sliding block 4 to the right, the strut 93 will be moved to turn the latch bar 9 counterclockwise. It becomes to be in a locking position. Then the opened and drawn out drawer cannot be closed unless the cylinder 1 is opened again. When trying to close the opened drawer by force, the latch hook 6 will hit the latch bar 9 and may become damaged. It could become an annoyance to users.